Monoplane kite



July 14, 1925.

C. DAHL MONOPLANE KITE Filed Sept. 20. 1923 Patented July 14, 1925.

UNITED STATES PATENT OFFICE.

CONRAD DAHL, OF CHICAGO, ILLINOIS, ASSIGNOR T0 ROBERT N. BURTON, O

CHICAGO, ILLINOIS.

.. MONOPLANE KITE.

Application filed September 20, 1923. Serial No. 663,750.

To ,all whom, it may concern:

Be it known that I, CONRAD DAHL, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Monoplane Kites, ofwhich the following is a specification, reference being had to theaccompanying drawings forming a part thereof.

This invention represents an improvement and refinement of the kitedesign shown and described in my application for Letters Patent, SerialNo. 636,823, filed May 5, 1923, and it has for its object the furthersimplification of the device for manufacture and the improvement of itssteadiness and efliciency in use. I

;It consists of certain features and elements of the construction hereindescribed and shown in the drawings, as-particularly indicated by theclaims.

In the drawings:

, Figure 1 is abottom plan view of the kite embodying this invention.

Figure 2 is a front elevation of the same.

Figure3 is a side elevation showing the kite-approximately in theposition of flight.

Figure 4 is a perspective view of the kite as seenifrom above.

Figure 5 is a detail view illustrating a feature of construction.

Figure 6 is a fragmentary side elevation showing the attachment of therudder plane toa vertical strut and the mid rib.

The framing for this kite consists of a longitudinal mid rib, 1, towhich a cross arm, 2, is attached near its forward end, while a crossarm, 3, similar in length to the arm, 2, is supported at a distanceabove the mid rib, 1, by securement to a vertical strut, 4, rising fromthe mid rib and partially held in'this position by lateral guys, 5,extending from its upper end to the outer ends of the cross arm 3. Guys,6, extend from the forward end of the mid rib, 1, to points on the crossarm, 2, at opposite sides of its mid point, and guys, 7, similarlyconmet the cross arm, 3, with the rear end of the mid rib, 1. By meansof these guys, 6 and 7, a main sail, 8, is held in stretched conditionbetween the cross arms, 2 and 3, being attached to the forward crossarm, 2, substantially throughout its width by a hem or like tubularconnection at 9, while its rear edge is connected to the arm, 3, atopposite ends of the latter by short strings engaging eyelets, 10, inthe'corners oftlie sail, 8. Inwardly from these points similar stringsengage eyelets, 11,in the rear edge" of the sail for anchoring to thecrossarm, 3, with the material unattached between the eyelets, 10 and11, to permit a slight swelling of the sail under wind pressure, allowing the wind to escape at therearedge tween these points of anchorageinstead of forming a pocket in the sail. I

Still nearer to the mid rib, 1, than the eyelets, 11, the sail isprovidedwith eye: lets, 12, through which a continuou's'cord, 13, passesfreely with its ends secured at 14, 14:, to the cross arm, 3. Theportion'of the sail between the eyelets 12, .12, extends downwardlyaround theunderside of the mid rib at 16, thus forming itself into'u'p}wardly diverging plane portions 17, 17, which tend to deflect the windequally. to the two broad areas of the sail, which are stretched in thecommon place of the cross arms, 2 and 3. The middle portion of the sailis left unattached to the mid ribat 16, so that in view of the freesliding engagement of the cord, 13, with eyelets, 12, the sail canadjust itself so as to equalizethe tension at the several points ofattachment, and its two main areas at opposite sides'of the mid rib willpresent substantially similar surfaces to the wind. v

A triangular jib sail, 18, is' attached to the main sail, 8, at 18 withits'apex extending forwardly for securement'to the. forward end of themid rib, 1. 'The sail, 18, thus lies in the common plane of the crossarm, 2, and the mid rib, 1, and thus stands at an angle to the principalplane of the sail, 8, forming a small banking plane against which thepressure of the wind will tend at all times to hold the forward end ofthe kite tilted upwardly as shown in Figure 3. 1

The cross arm, 3, is attached to thestru't, 4, preferably by readilydisengageable means. As shown in Figure 6, the strut is notched at 20 toreceive the cross arm which is bound in position by a string 21, wrappedabout both members. If desired, a second notch, 22, may be provided at alower point in the strut, 4, so that for certain condltions the crossarm, 3, may be mounted in this lower position to alter the angle of themain sail, 8. This adjustment may be made when it ;is desired-to {flythe fllqit'e' .in a -.particularly heavy Wind;

The remainder of the construct-ion is also devised .to permit the partsto be quickly disassembled for convenience in transporting the kite fromplace to place. The upper end of the strut, 4, is formed with a notch,23, having a middle enlargement, 23, formed by drilling a hole into theend of theatrnt; the guy string, has a knot, 5, tied at 'its nid point,so that when the string is ed inthe notch, 23, the knot will eenlargement, 23 and thus anchor the in the strut. ,A similarconstrnction'may be applied to the ends of the mid I M 2 and facourateengagement .of the guy strings, 6 and '7. I

For steadyin'g. the kite and giving it a a single piece ,ot' cloth orpaper folded about thejfmjid rib,' l, to ,torm .acsleeve, 32,engagingit,:thusfmaking ,the rudder pori l 911,30, of donbleithicknesswith the bankin W ngs, ,3l,y,tcl of s g e thickness, to da ou tmmitnpperedge. For stiffenng ,tl rudder plane aireenforcing strip, 33, ofwood rnay he attached exteriorly as shpwn, or may ,be glued in positionhetyxeelltl fi wo plies of the plane, 30.. The upper and t ward corn ofsaid plane is amhQr d-totlw cross arm, y @s ring, 34:, engaging aneyelet, 35,, in the plane, 30. Similarly an eyelet, 3.6, at the rearcorner of the lane receives a string, 37, extending to the cade the midrib, 1-

"For holding the kite in flight, I provide a pair of st ings, 0., 40.,extend ng f th cross arm, 2, substantially at the points at nih ah guys6, 6,.a11 con e ed; a third ring, 51:1, extends from the extreme rearend of the mid rib,'1, and these three strings are tied to a shortequalizer bar, 42. the string, 4:1, to its mid point, and the strings,i0, to its opposite ends. The main leading string, i3, is attached tothe mid point of the bar, 42, as shown in Figures 2 and 3.

I cla m:

1. In a kite, th Combination of a longitudinal mid-rib, a cross armsecured thereto near the forward end, a second cross arm positionedrearwardly of the first and spaced above the, common plane of said firstcross arm and the mid-rib, a main sail stretched between said cross armswith most of its area disposed in their common plane but having itsmiddle portion drawn down- Wardly to the :mid-rib ifoinlning ia pair ofupwardly flaring surfaces to deflect the wind to both lateral areas ofthe main sail.

2. In the combination wdefined i'nroieim said imain sail being attachedto the first cross arm substantially throughout its width and beingattached to the second cross arm at: its corners and at two other pointsequidistant from the mid rib.

3. In the combination defined in claim 1, said ll'liClCllG portion ,ofthe main sail being unattached to the mid-rib and being laterallydefined by a pair of .eyelets in the sail at its rear edge and atopposite sides of the mid-rib with a cord passing freely through saideyelets above the mid-rib and having its ends anchored to the secondcross arm.

4. In the combination defined in claim '1 a triangular jib sail orbanl'cing planeIe'xtending forwardly from the main sail at the firstcross arm with its apex attached to forward end of the m'id-riib wherebysaid jib sail extends forwardly and upwardly at an angle with respect totheprincipal plane of the main sai'.

5. In the combination defined in claim .1, a triangular jib sail orbanking plane .inclined upwardly from the main sail at the first crossarinwith its apex attachedtot'he forward end of the mid-rib and'a pairof bani-ting planes supported rearwardlyof .the main sail at oppositesides of the vertical plane of the midrib and also inclined upwardlywith respect to the principal plane of said main sail.

i. In the combination defined in claim 1, said mid-rib extendingrearwardly of the second cross ar-m. guys connecting the rear end ofsaid mid-rib with laterally separated points 'on the cross arm, arudderplane upstanding from the mid-rib substantially to the height of thesecond cross armabove the mid-rib and tapering-down toward the rear withbanking planes extending from .both sides f said rudder to the guys.

7. In a kite. the combination of a longitudinal midrib, across armsecured thereto near the forward end, a second cross arm positionedrearwardly of the first and spaced above the common plane of Said firstcross arm and the mid-rib, a main sail stretched between said cross armsat an angle to said common plane, said mid-rib extending rearwardly ofthe second cross arm. banking sails disposed above the rearwardlyextending portion of the mid-rib at both sides of its vertical plane andinclined downwardly from the plane of the main sail and a leading stringextending from the middle of an equalizer bar with a pair of stringsconnecting the ends of said bar with the first cross arm at oppositesides of its middle and a third string ext-ending rearwardly to the rearend of the mid-rib.

8. In a kite, the combination of a longitudinal mid-rib, a cross armsecured thereto near the forward end, a second cross arm positionedrearwardly of the first and spaced above the common plane of said firstcross arm and the mid-rib, a main sail stretched between said arms, arudder plane upstanding from the mid-rib and banking planes disposedfore-and-aft of the main sail respectively inclined forwardly andupwardly and rearwardly and downwardly with re spect thereto.

9. In a kite. the combination of a longitudinal mid-rib. a cross armsecured thereto near the forward end. a second cross arm positionedrearwardly of the first and supported above it by a vertically extendingstrut, said strut having a notch to accommodate the cross arm and asecond notch at a different distance from the mid-rib and means forretaining said cross arm in either notch together with a main sailadapted to be stretched between said first and second cross arms andbanking planes mounted fore-and-aft of the main sail respectively infixed angular relation to the common plane of the mid-rib and the firstcross arm.

In testimony whereof. I have hereunto set my hand at Chicago. Illinois,this 18th day of September, 1923.

CONRAD DAHL,

